D a ta S he e t
5 0 0 m A H y s t e r e t i c H i g h Vo l ta g e St e p - D o w n C o n v e r t e r
with Dual Power Monitor
1 General Description
2 Key Features
The AS7620 is an easy-to-use, high-efficiency, highvoltage, hysteretic step-down DC-DC converter,
operating in asynchronous mode. Its low-power
architecture extends hold-up time in battery-backed and
critical applications where maximum up-time over a wide
input supply voltage range is needed, while still
providing for high efficiencies of up to 90% during peak
current demands.
Low quiescent current for efficient partial load
Although the AS7620 is optimized for 24V applications
found in industrial and medical systems, its ability to
support 100% Duty Cycle makes the AS7620 ideal for
applications demanding maximum up-time and soft
power fail behavior. In combination with low idle current
of only 30µA, on-demand switching reduces operating
current at low load currents.
Resistor-programmable Early Power Fail Warning
Wide Supply Voltage Range, 3.6V to 32V
100% Duty Cycle extends operating range
Pin-programmable cycle-by-cycle current limit
Integrated PMOS eliminates bootstrap capacitor
Power-Good Flag
Thermal Shutdown
Fixed 3.3V and adjustable output (1.2V to VIN)
Small 4x4mm 12-Lead MLPQ Enhanced Power
By selecting an appropriate inductor value, operating
current can be lowered and switching frequencies tuned
to certain load conditions.
Specified from -40ºC to +125ºC junction and 85ºC
maximum ambient temperatures
A pin-strapped current limit input minimizes inductor
peak current and thus inductor size and cost for any
given application.
3 Applications
The device further includes output short-circuit
protection and thermal shutdown. In shutdown mode,
only 1µA (typ) of current is consumed.
The AS7620 is suitable for Industrial 24VDC
applications like PLCs, robotics; Home Security and
Building Control applications; Solid-state utility meters;
Signage and LED column power; and Sensor interfaces.
Figure 1. Block Diagram
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Data Sheet - O r d e r i n g I n f o r m a t i o n
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Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing
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the information set forth herein or regarding the freedom of the described devices from patent infringement.
austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice.
Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for
current information. This product is intended for use in normal commercial applications. Applications requiring
extended temperature range, unusual environmental requirements, or high reliability applications, such as military,
medical life-support or life-sustaining equipment are specifically not recommended without additional processing by
austriamicrosystems AG for each application. For shipments of less than 100 parts the manufacturing flow might show
deviations from the standard production flow, such as test flow or test location.
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Contact Information
austriamicrosystems AG
A-8141 Schloss Premstaetten, Austria
Tel: +43 (0) 3136 500 0
Fax: +43 (0) 3136 525 01
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